著者

Lesk V. I. Aoki S. Burkhalter R. Fukugita M. Ishikawa K.-I. Ishizuka N. Iwasaki Y. Kanaya K. Kuramashi Y. Okawa M. Taniguchi Y. Ukawa A. Umeda T. Yoshie T.

出版者

American Physical Society

雑誌

Physical review D (ISSN:05562821)

巻号頁・発行日

vol.67, no.7, pp.074503, 2003-04

被引用文献数

16

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We present results for the mass of the η′ meson in the continuum limit for two-flavor lattice QCD, calculated on the CP-PACS computer, using a renormalization-group-improved gauge action, and the Sheikoleslami-Wohlert fermion action with a tadpole-improved csw. The correlation functions are measured at three values of the coupling β corresponding to the lattice spacing a≈0.22, 0.16, 0.11 fm and for four values of the quark mass parameter κ corresponding to mπ/mρ≈0.8, 0.75, 0.7, 0.6. For each (β, κ) pair, 400–800 gauge configurations are used. The two-loop diagrams are evaluated using a noisy source method. We calculate η′ propagators using both smeared and local sources, and find that excited state contaminations are much reduced by smearing. A full analysis for the smeared propagators gives mη′=0.960(87)-0.248+0.036 GeV in the continuum limit, where the second error represents the systematic uncertainty coming from varying the functional form for chiral and continuum extrapolations.